In combat operations, it is often difficult to determine friend from foe. Currently, two separate systems are in use: an active IR beacon and a passive IR reflector. The IR beacon is turned on and off at the command of support aircraft in order to prevent unfriendly forces from observing the active IR beacon and cloning it thereby to spoof air support into believing the enemy is part of a friendly force.
The passive IR reflector enables locating personnel that may be incapacitated and unable to respond directly to search and rescue. Unfortunately, if incapacitated personnel are captured and sheltered from observation, it becomes extremely difficult to locate and rescue them.